72 Ohscrvations on Parasites and Parasitic Diseases, S\-c. 



found that, " in the course of two years, they had increased so 

 enormously that they occupied every cutaneous follicle, and the 

 dog^ became in consequence quite naked." The correctness of 

 these deductions has, however, been doubted by both 'Simon 

 and Neal. 



Professor Weiss, of the Veterinary School of Stuttgart, holds 

 opinions in accordance with our own, i.e., that disease of the 

 skin of the dog is occasionally induced by these parasites. He 

 relates cases in point, and says that the Acari ultimately destroy 

 the hair-producing organ, so that hairs do not again grow on the 

 bald places. It appears also that he considers it just possible 

 that the Acari may travel after long habitation from a diseased 

 to a healthy animal ; still, as he observes, it is easy to deny the 

 contagiousness of the affection induced by their presence. He 

 adds, that in Haubner's experimental attempts to propagate the 

 malady by transmission of the animalcula*, a failure occurred in 

 both instances. 



In concluding our remarks on the Acarus Folliculorum, we 

 may state that the destruction of the parasite is effected with 

 great difficulty, arising chiefly from the circumstance of its being 

 enabled so easily to make its way to the extieme ends of the 

 hair follicles and sebaceous glands. Success in destroying the 

 Acari depends very much more on the manner in which medicinal 

 agents are used than on the agents themselves. The most potent 

 destroyers of their life may prove perfectly inert unless pro- 

 perly applied. Nothing short of a thorough rubbing in of whatever 

 be used will suffice ; and not only so, but it is necessary for the 

 agent to be applied again and again. An ointment made with half 

 a pound of lard, two ounces of tar, and four ounces of sulphur 

 should be well rubbed in before the fire, or in the sun to assist its 

 penetration into the follicles of the skin. The unguent should 

 also be allowed to remain on the skin for two or three days, and 

 more fi'iction applied daily. When washed off, some carbonate 

 of potash should be used with the soap and water so as to 

 thoroughly cleanse the animal. The skin should then be dried, 

 and recourse had again to the unguent. This treatment must be 

 repeated for at least three or four times. 



Beyond topical applications none are absolutely required, as 

 success depends exclusively upon the destruction of the Acari 

 and their ova. It should, however, be borne in mind that many 

 of the parasites may survive and yet no evidence of their existence 

 be observed perhaps for several weeks. For this reason the treat- 

 ment should be repeated at certain short intervals, even in those 

 cases where the dog appears to have recovered. 



(To he continued.') 



